Sensors and other devices may need to be authenticated. Authentication may ensure that a data source is transmitting data to a valid destination and that the data therefore remains secure. Authentication may also ensure that data is only received from trusted sources.
A physical unclonable function (PUF) includes circuitry configured to generate an output whose value depends on unique physical properties of the circuitry. Even tightly controlled manufacturing processes will include variations. Thus, even when circuit components are intended to have identical characteristics, these variations result in circuit components with unique characteristics.